Automatic tool releasing clutch



April 21, 1953 c. M. CHAPlN 2,635,260

AUTOMATIC TOOL RELEASING CLUTCH Filed Feb. 21, 1948 2 SHEETS-SHEET 1 BY@7 W ATTORNEY.

C. M. CHAPIN AUTOMATIC TOOL RELEASING CLUTCH April 21, 1953 Filed Feb.21, 1948 2 SHEETSSHEET 2 FIG. 8.

54 FIG. 12.

INVENTOR.

CHESTER M. CHAPIN BY A2 54 r ATTORNEY.

tation .of the machine.

Patented Apr. 21, 1953 AUTOMATIG TOOL RELEAS'ING CLUTCH. f I ChQSterMQQhapin, St. isms, Mp, V Applicatio'n February 21, 1943; Serial N61lit-15.4 Q

' teens. (c1. T104789) The invention relates to'fldevices for; mountingthreadingtools, suchas taps and dies, and for .ause on-Jathes, drillpresses or other machines having rotatin'g spindles to provide-relativerotation between the tool and .a work piece to be threaded. i

' One objectof theinvlention is to automatically stop the threadingofiawork pieceiat any .de-

sired point without: stopping. rotation .of the machine in whi'ch thedevice is used.

- 1 Another object' is to. withdraw the. threading tool from the Workpiece when threading is completed merely by reversing. the direction ofro- Another object is. touprosiide aproauctionitael forrapid and uniformthreading of :.each of .a number .of. substantially identical work'pieces.

Other obj ectswill be apparent to .those skilled in the art. from thefollowing description and accompanying drawings, inmhioh: r

.xFigure 1 is atop view of a deli/ice constructed according to theinvention andprovided witha die :for threading aworkpiece. i i 11 Figure:Zisa longitudinal vertical sectienxtaken approximately on the line 2--2of Figure ,1 and 1 apredeterminedllen thg Figures iii-5. and ,6 aretransverse we a1 sections taken rapproximatelynn the lines... 5-5 and6fi.,,resp ctive1y, .of .Ei uiie Figure 7 is a p rsp ctiveiof a holder.ior the tool and shows a clutch .fece .formed in holder,

,Figure '8 is a section on the 8m Figure 7 developed into a plane... i I.1

Fi ure 9 is a view. simi a to .Fi ur :2 and shows the device with.another.;irm o clu ch and with an adapter iormounting a tap. Figure 10is an end ilieweqftheholder for the tool in Figure 9 and shows theassociated clutch face. i h i Figure '11 is aside view of the holdershown in Figure .10, t

Figure 1.2 is a sectionon the annulus 1:201 fi u e 1. d e ped into a plaeflh to un ing de e I shswn n Fi ur s 1+8 is held a nst rotation n tails ock 2 of a la he and mo nts a d e 3 for th a in a r tatin w piece .4 munt d n a iisk the ead st k ot s o n) o e he; The dse comp se acylindrical base .5 having a axial bore .6 extending therethrough:.and,.a collar 1 at one of its ends ad te iOr-i iinfih the devic en tal st k .2 e nd i t h e at the .ot er end o ihsbase and. s se med t thebas by set. cr ws.

.A holde is rotat ble .9 base; seas collar .1 a d ex ds rwa ly of t e dac n end o the Dis 3 rece ved in th g iwa d end Dimm r l0. an is uis a;.h0l .;1@. -JJ A s screw 12 e ures di it? 119 s?! 1 sr w i sl tted atup myi a .11 h res ns of thread se t n s and ot er preiss m terielon or.morearcuste ecsssss1 e s term in: the .ie t-hah as o ho de 0 71. sho deri5 Iit. o s fiersnids th, is ih 'n oppos te ,d res iqhs ensi arl 9f, as.b 1 sho ld r 5 ex nd in a d .i sm. he se ies? f. 110. 5. shoi lder .6ext nds inwar y of holder -flj om. a po nt at t sis s 1 2 2 t m o shoder 1.5 ro ves .1 s ope i 0P- pp its d re t ons fr m the inn r en s shoude s l5 and L6. to the se ies? Qf .h9l x 9 r and .e psvssqlks o rom t eter $1. 9 o houlde 16. t thesi rfase ,9; helq sr t" at. ad ac ntshoulder l5.

..wii h l e 0,-

secur snssssn a es V len th se ms sm nt 9f r-JD sel e s .A rise 2.0slides on b ss 5 s as 1 .leev i9 m sse a lun er. .21 y 9 e base t ugh apass ge ??..in slssteJ? and gr o es 14- A comp ess n s in 2' inp s e2.2. rs plun e 2. in o e s s L 2 hrusts, r sifl against slee e .J. ..Abe t 3.4 is moun ed 9 1. ri g .2 diametrically ppes s. p un e and etends into a assa e 2 in sle ve L8,. To r vent this ;.2@. 'i Qm.r s.1-iep h sefi. unde t tensi n at prin .2 asimila "s in z ssiq s r eifi ismqunted on bolt 2. pas e 25 andihriher thrusts rin 20 a ainst s eeve '1Aasin 2 diametric lly t r u rin 2.01am Jesse. A .set screw its holds p n12'] ass m led tearin .-,21fl. Ease 5 is slot ed 1 0m situdin il'y at 8accommoda e pin i]- and provide slid n mo eme t of rin 0.- An elongatedpiston slides within bore 18 in hasesfi. :Piston 29 includesacylindrical part 30 ,slidable in here .6 and having a threaded passage31- receiving a. threaded :tube -32; A.

screw 3:3 isthreaded into the other .endtof piston 29 andengages pin 2].A..screw :34 is-ithreaded into tubefland engages work piece 4 near theend of a threading operation as shown in Figure 3. Pant:: 30;;tube.S-Zand-scriaws :33 and 34 may be rgtatedwrelative toone'another toadjust the to the left of shoulder I6. -tion of rotation of the machineis reversed, sleeve 3 effective length of piston 29, of which they forma part, and are maintained in adjustment by set screws 35. The effectivelength of piston 29 determines the length of thread on work piece 4.Work piece 4 normally is disengaged from piston 29 until just prior tothe end of the threading operation when work piece 4 engages screw 34 ofpiston 29 and moves piston 29, ring 28 and plunger 2| toward tail stock2 until plunger 2| is disengaged from shoulder l6, as shownin Figure 3.Holder l8 then rotates with work piece 4 in a counterclockwise directiondue to the friction between the work and the holder die (Figures 6- and7). Plunger 2| slides on the inclined portion of groove I4 to the leftof shoulder l6 (Figure 6)- and is moved outwardly to the surface of.holder It at |8, drops into a groove l4 adjacent shoulder l5, slides onthe inclined portion of the groove adjacent shoulder l and is againmoved outwar'dly tothe end surface of holder H1 at IT,

thenslides inwardly on the inclined portion of the next groove until itsmovement is limited by ring 20 but clears shoulder I6 and again slidesoutwardly on the inclined portion of the groove When the direcwhile workpiece 4 is unthreaded therefrom.

The device shown in Figures 9-12 is mounted for rotation in the chuck 41of a drill press and for threading a stationary work piece 6|. Thedevice is substantially thesame as the device shown in Figures 1-8except that a pair of plungers 48 are mounted diametrically opposite ona ring" 49 and extend through passages 58 in asleeve 5| rigid with base52. Plungers 48 are urged by springs 53 into annular grooves 54 in atool holder 55 for engagement with pairs of opposing shoulders 56 and51. The shoulders of each pair are positioned diametrically opposite.

Shoulders 56 are approximately half the height of shoulders 51 whichextend inwardly from the surface of holder 55. The bottoms of theshoulders are at the same level but shoulders 56 are approximatelyone-half the height of shoulders 51. The portion 54b of one'groove 54between the inner ends of each shoulder 56 and the associated shoulder51' is substantially uniform in depth. Grooves 54 slope outwardly fromthe outer ends of shoulders 56 to the surface of holder 55 at 54a.

Holder 55 mounts an adapter 58 provided with atap 59 for threading arecess 60 in a work piece 6|. Adapter 58 comprises a tube 62 shoulderedat 63 and abutting an associated shoulder 64 in holder 55. A look screw66 secures tube 62 to holder 55. A pin 65 extends diametrically throughtube 62 within tool holder 55 and rigidly mounts a cylindrical tapholdingelement 61 and slidably mounts a cap 68 for engaging 'work piece6| just prior to recess 60 being threaded to a desired depth. .Tap 59.is held in element 61 by a set screw .69. Cap 68 comprises a part and apart 1| threaded together so that the overall length of cap 68 may beadjusted. Aset screw 12 holds the parts 18 and 1| against relativerotationafter adjustment; Cap 68 engages a piston l3 slidable in base52.

When the threading of recess 68 has proceeded to a desired depth, piston13 moves ring 49 away from sleeve 5| until plungers 48 are disengagedfrom shoulders 56 and base 52 rotates relative to holder 55. Plungers 48slide in a clockwise direction (Figure 10) over the out-- wardlyinclined portions of grooves 54 adjacent shoulders 56 to the surface ofholder 55 at 54a, then drop into grooves 54 adjacent shoulders 51 at 54buntil their movement is limited by ring 49, clear shoulders 56 andslideon the out-' wardly inclined portions of grooves, 54 adjacent"movement of the tool.

The device may be adjusted for threading a work piece any desireddistance and the device may be used in production for rapid and uniformthreading of each of a number of approximately identical work pieces.

The size, depth, and arrangement of the grooves and other details ofconstruction may be varied substantially without departing from thespirit of the invention, and the exclusive use of those modifications:coming within the scope of the claims is contemplated.

What is claimed is:

1. In a device of the kind described, a cylindrical base having an axialbore, a holder for a threading tool rotatably mounted on the base butnon-slidable thereon, said holder having an end facing longitudinally ofthe base and provided with arcuate grooves, the bottoms of said groovesbeing inclined relative to the end of the holder and having stepsforming lateral shoulders facing in opposite directions, a. cylindricalsleeve surrounding the base and having longitudinal passages at oppositesides of the base and opposite to said grooves, spring thrust plungersslidable in said passages and projecting from the end of the sleeve intosaid' grooves and having reduced diameter portions slidably fitting inthe opposite end of the sleeve and projecting therefrom, a ringsurrounding and slidable on the base, said plunger portions beingsecured to the ring, a pin and slot connection between the ring and baselimiting the sliding movement of the ring on the base and holding themagainst relative rotation about the axis of the base, and an elongatedelement movable longitudinally of the base and having oppositeextremities disposed to engagelthe work and the pin connection betweensaid ring and base to move said ring and plungers away from the groovedend of the sleeve to free the plungers from the lateral shoulders.

2. A device as described in claim 1 in which the grooves have oppositelyfacing shoulders of different heights, there being means limiting themovement of the elongated element to clear the I projecting plungersfrom the lower of said shoulders but not from the higher of saidshoulders.

3. In a rotating tool mechanism of theclass described, a base memberhaving an axial bore, a ring surrounding said base member and slidablethereon, the base member having .a longitudinal slot abreast of saidring, a pin extending diametrically through said ring and slot, a sleevesurrounding saidjbase member and fixed thereto,

elongated passages in said sleeve at opposite sides of the base member,spring-thrust plungers in said passages and projecting therefrom andconnected to said ring to limit the spring-thrust movement of saidplungers, and a tool holder rotatably mounted upon the base and havingarcuate grooves in an end opposite to said sleeve and adapted to receivesaid plungers, said grooves being shouldered to engage the sides of saidplungers, and a thrust element surrounding and rotatable on said toolholder and slidable thereon and in said base and adapted to engage thework at one end and said ring pin at the other end to shift said ringand plungers relative to said tool holder.

4. A rotating tool mechanism as described in claim 3 in which the thrustmember comprises a plurality of parts, adjustable lengthwise of themechanism, and locking means therefor to vary the effective length ofthe thrust member according to the desired movement of the tool alongthe work, the tool holder having lateral openings spaced from its toolholding portion longitudinally or the mechanism and providingunc/bstructed access from the exterior or the mechanism to the lockingmeans for such adjustment.

CHESTER M. CHAPIN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 496,420 Leland May 2, 1893 671,447 Morgan Apr. :9, 1901796,205 Graham Aug. 1, 1905 915,201 Miller Mar. 16, 1909 915,568 DouglasMar. 16, 1909 991,785 Klocke May 9, 1911 1,045,598 Oatman Nov. 26, 19121,463,497 Bugatti July 311, 1923 2,040,344 Stull May 12, 1936 2,406,204Dansel Aug. 210, 1946 FOREIGN PATENTS Number Country Date 50,860Switzerland May 21, 1910 462,587 Great Britain Mar. 11, 1937

